@article{GDZPPN002228378,
title = {A "Birkhoff-Lewis" type result for a class of Hamiltonian systems.},
journal = {Manuscripta mathematica},
volume = {58},
year = {1987},
pages = {441-456},
zbl = {0616.58014},
url = {http://dml.mathdoc.fr/item/GDZPPN002228378}
}
Benci, Vieri; Fortunato, Donato. A "Birkhoff-Lewis" type result for a class of Hamiltonian systems.. Manuscripta mathematica, Tome 58 (1987) pp. 441-456. http://gdmltest.u-ga.fr/item/GDZPPN002228378/